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Rivers are vital freshwater resources that cater to the needs of society. The burgeoning population and the consequent land-use changes have altered the hydrologic regime with biophysical and chemical integrity changes. This necessitates understanding the land-use dynamics, flow dynamics, hydrologic regime, and water quality of riverine ecosystems. An assessment of the land-use dynamics in the Aghanashini River basin reveals a decline in vegetation cover from 86.06% (1973) to 50.78% (2018). The computation of eco-hydrological indices (EHI) highlights that the sub-watersheds with native vegetation had higher infiltration (and storage) than water loss due to evapotranspiration and meeting the societal demand. The computation of water quality index helped to assess the overall water quality across seasons. The study provides insights into hydrology linkages with the catchment landscape dynamics to the hydrologists and land-use managers. These insights would aid in the prudent management of river basins to address water stress issues through watershed treatment involving afforestation with native species, appropriate cropping, and soil conservation measures. [ABSTRACT FROM AUTHOR]

Streamflow can be affected by a number of aspects related to land use and can vary promptly as those factors change. Urbanization, deforestation, mining, agricultural practices and economic growth are some of the factors related to these land use changes which alter the stream flow. In the present study, the impact of land use land cover change (LULC) on stream flow is studied by using SWAT model for Tungabhadra river basin, located in the state of Karnataka, India. Tungabhadra river originates in the Western Ghats of Karnataka and flows towards north-east and joins the river Krishna. The land use maps of 1993, 2003 and 2018 are used for assessing the stream flow changes with respect to LULC. Calibration and validation of the model for streamflow was carried out using the SUFI-2 algorithm in SWAT-CUP for the years 1983–1993 and 1994–2000 respectively. Statistical parameters namely Coefficient of Determination (R2) & Nash–Sutcliffe (N-S) were used to assess the efficiency and performance of the SWAT model. It was found that the observed and simulated streamflow values are closely matching, which in turn projects that the model results are acceptable. The calibrated model was used for simulation of future dynamic land use scenario to assess the impact on streamflow. The results can be used for conservation of water and soil management. [ABSTRACT FROM AUTHOR]

Wildlife corridors are critical in maintaining ecological processes and wildlife management, but they are fragmented and degraded due to various land-use practices. It is crucial to restore wildlife corridors through participation of communities/institutions of the landscape. Ironically, however, most of the proposed conservation plans are devoid of them in conservation and policy-making. Therefore, valuing the onus of people and their inputs to restore and manage wildlife corridors would be a practical strategy. We are addressing this 'restoration initiative' in the Biligiri Rangaswamy Temple Tiger Reserve, Karnataka, India by integrating knowledge from social and ecological sciences. The preliminary result indicates that, people and institutions from the landscape are willing to support the restoration efforts. This initiative would emerge as one of the successful, actionoriented and policy-driven projects in this landscape. [ABSTRACT FROM AUTHOR]

The Cauvery basin of Karnataka State encompasses a range of land cover types, from dense forest areas and plantations in the Western Ghats hills, to fertile agricultural lands in the river valley. Recent demographic changes, rapid economic development and urbanization have led to the conversion of vast stretches of forested land into plantations and permanent agriculture. We examine the human drivers of forest cover change between 2001 and 2006, using MODIS 250 m data at multiple spatial scales of nested administrative units i.e., districts and taluks. Population density does not emerge as a major driver of forest distribution or deforestation. Protected areas and landscape accessibility play a major role in driving the distribution of stable forest cover at different spatial scales. The availability of forested land for further clearing emerges as a major factor impacting the distribution of deforestation, with new deforestation taking place in regions with challenging topography. This research highlights the importance of using a regional approach to study land cover change, and indicates that the drivers of forest change may be very different in long settled landscapes, for which little is known in comparison to frontier forests. [ABSTRACT FROM AUTHOR]

Assessment of stream flow dynamics reveals principal characteristics of a river basin as it results from a complex blend of hydrological drivers. Earlier studies suggest climatic parameters and land use changes are the major causes of river flow changes in the basin. However, introduction of large-scale irrigation and other irrigation management activities in the basin will also play a crucial role in stream flow variations. The present work aims to understand the contributions of these drivers towards decreasing river flows in the Malaprabha river basin, Karnataka, India. Results of the Mann-Kendall trend test showed non-significant decreasing trends in annual and seasonal rainfall patterns in the area. The effect of Land Use /Land Cover (LU/LC) change on stream flows was analyzed using decadal LU/LC maps for the period 1985,1995 and 2005 as inputs to the Soil Water Assessment Tool (SWAT) hydrological model. Further, the effect of Malaprabha reservoir on stream flows was analyzed by performing SWAT simulations for with and without reservoir conditions. The comparative analysis showed that there is negligible contribution of decadal LULC on river flows. However, the presence of the reservoir was found to be contributing 43% of stream flow variability. This study revealed that at catchment scale reservoir storage and related operational activities affects the river flows more significantly than LULC changes. [ABSTRACT FROM AUTHOR]